If you are ever arrested for a DUI, the last thing you may be thinking about is whether the police officer who arrested you was unlawful in making the arrest. If the officer was unlawful, though, it may be enough to get your charges dismissed.

Unless you commit a traffic violation, such as speeding or running a red light, a police officer can only pull you over if he or she has reasonable cause to believe you are driving under the influence of alcohol. Reasonable cause is a very broad term, but some of the things that police officers look for can include:

  • Swerving
  • Weaving in between lanes
  • Endangering other vehicles
  • Following other vehicles too closely
  • Driving well under the speed limit
  • Erratic braking

By exhibiting any of these actions, you can give a police officer reasonable cause to assume you're driving under the influence.

If you are pulled over or are stopped at a sobriety checkpoint stop, remember that a police officer cannot search your vehicle without your consent. As a United States citizen, the Fourth Amendment to the Constitution protects you from unlawful stops and unreasonable searches.

The only way a search of your vehicle is legal without your consent is if the police officer can see an open alcohol container from outside the car. Otherwise, any search of your vehicle without your consent is unlawful. If such a search were to occur and lead to your DUI arrest, an experienced DUI attorney would be able to fight your arrest and your charges may even be dropped because of the police officer's unlawful actions. Should any evidence against you have been collected in an unlawful search, it would not be admissible in court.